﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading;
using System.Net.Sockets;
using System.Net;
namespace ListenServer
{


    class Server
    {
        //创建一个和客户端通信的套接字
        static Socket SocketWatch = null;
        //定义一个集合，存储客户端信息
        static Dictionary<string, Socket> ClientConnectionItems = new Dictionary<string, Socket> { };
        public static string cID;
        public Server()
        {
            //端口号（用来监听的）
            int port = 9190;
            IPAddress ip = IPAddress.Any;
            //将IP地址和端口号绑定到网络节点point上  
            IPEndPoint ipe = new IPEndPoint(ip, port);
            //定义一个套接字用于监听客户端发来的消息，包含三个参数（IP4寻址协议，流式连接，Tcp协议）  
            SocketWatch = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
            //监听绑定的网络节点  
            SocketWatch.Bind(ipe);
            //将套接字的监听队列长度限制为20  
            SocketWatch.Listen(20);
            //负责监听客户端的线程:创建一个监听线程  
            Thread threadwatch = new Thread(WatchConnecting);
            //将窗体线程设置为与后台同步，随着主线程结束而结束  
            threadwatch.IsBackground = true;
            //启动线程     
            threadwatch.Start();
            Console.WriteLine("开启监听......");
            Console.WriteLine("点击输入任意数据回车退出程序......");
            Console.ReadKey();
            SocketWatch.Close();
        }
        //监听客户端发来的请求  
        static void WatchConnecting()
        {
            Socket connection = null;
            //持续不断监听客户端发来的请求     
            while (true)
            {
                // string cID;
                try
                {
                    connection = SocketWatch.Accept();
                }
                catch (Exception ex)
                {
                    //提示套接字监听异常     
                    Console.WriteLine(ex.Message);
                    break;
                }
                byte[] idrec = new byte[1024 * 1024];
                int length = connection.Receive(idrec);
                cID = Encoding.UTF8.GetString(idrec, 0, length);
                ClientConnectionItems.Add(cID, connection);
                //显示与客户端连接情况
                Console.WriteLine("\r\n[客户端\"" + cID + "\"建立连接成功！ 客户端数量：" + ClientConnectionItems.Count + "]");
                //获取客户端的IP和端口号  
                IPAddress clientIP = (connection.RemoteEndPoint as IPEndPoint).Address;
                int clientPort = (connection.RemoteEndPoint as IPEndPoint).Port;
                string sendmsg = "[" + "本端：" + cID + " 连接服务端成功！]";
                byte[] arrSendMsg = Encoding.UTF8.GetBytes(sendmsg);
                connection.Send(arrSendMsg);
                //创建一个通信线程      
                Thread thread = new Thread(recv);
                //设置为后台线程，随着主线程退出而退出 
                thread.IsBackground = true;
                //启动线程     
                thread.Start(connection);
            }
        }

        static void recv(object socketclientpara)
        {
            Socket socketServer = socketclientpara as Socket;

            while (true)
            {
                try
                {
                    byte[] arrServerRecMsg = new byte[1024 * 1024];
                    int length = socketServer.Receive(arrServerRecMsg);
                    //将机器接受到的字节数组转换为人可以读懂的字符串     
                    string strSRecMsg = Encoding.UTF8.GetString(arrServerRecMsg, 0, length);
                    string ccID = strSRecMsg.Substring(0, 4);
                    int len = strSRecMsg.Length;
                    string hc = cID + ":" + strSRecMsg.Substring(4, len - 4);
                    Console.WriteLine(DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss:fff") + "]\r\n" + strSRecMsg);
                    //判断是否包含这个客户端
                    bool contains = ClientConnectionItems.ContainsKey(ccID);
                    if (contains)
                    {
                        ClientConnectionItems[ccID].Send(Encoding.UTF8.GetBytes(hc));
                    }
                    else
                    {
                        Console.WriteLine("输入有误，不予转发\r\n");
                    }
                    arrServerRecMsg.DefaultIfEmpty();
                }
                catch (Exception)
                {
                    string temp = ClientConnectionItems.First().Key;
                    //提示套接字监听异常  
                    Console.WriteLine("\r\n[客户端\"" + socketServer.RemoteEndPoint + "\"已经中断连接！ 客户端数量：" + ClientConnectionItems.Count + "]");
                    ClientConnectionItems.Remove(ClientConnectionItems.First().Key);
                    Console.WriteLine("\r\n[客户端\"" + temp + "\"已经中断连接！ 客户端数量：" + ClientConnectionItems.Count + "]");
                    break;
                }
            }
        }
    }
}
